linux-kernel - RE: [PATCH] ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 23 Aug 2017 14:56:46 +0000
From:   "Luck, Tony" <tony.luck@...el.com>
To:     Alan Cox <gnomes@...rguk.ukuu.org.uk>,
        Kees Cook <keescook@...gle.com>
CC:     "Rafael J. Wysocki" <rafael@...nel.org>,
        Len Brown <lenb@...nel.org>, Boris Petkov <bp@...e.de>,
        Tyler Baicar <tbaicar@...eaurora.org>,
        "Punit Agrawal" <punit.agrawal@....com>,
        "linux-acpi@...r.kernel.org" <linux-acpi@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] ACPI / sysfs: Extend ACPI sysfs to provide access to
 boot error region

>> Should this not also have a capability check. Assuming file permissions
>> are sufficient for grabbing a chunk of system memory holding error
>> info doesn't seem too scary but it's at odds with a lot of other cases ?
>
> At least one of those other cases (pstore) added a capability check and now regret
> it.  There's a thread on reverting it. Look for:
>
>   Revert "pstore: Honor dmesg_restrict sysctl on dmesg dumps"

Here's at least part of that thread:

https://marc.info/?l=linux-kernel&m=150301241114262&w=2

Kees: you were OK with removing the capability check from pstore, right?

I'm now adding another place to access a blob of memory containing
crash information from the previous kernel (pointed at by the ACPI
BERT record).

-Tony